Self Assessment is a system used by HMRC to collect income tax from some individuals. HMRC uses a form called a tax return to let people report their income to them usually via an online submission.
If you are asked to complete a tax return you need to meet deadlines and fulfil your responsibilities under self assessment to avoid penalties.
Getting your tax return wrong or missing a deadline can be costly which is why not using an accountant can be a false economy.
It’s not just self employed people who have to fill in a tax return. Some of the most common reasons why a tax return may be required are:
Hiring an accountant to complete and submit your tax return can give you a number of valuable benefits including:
We’ve listed below five significant advantages of using an accountant to submit your tax return:
Using all available tax reliefs and allowances makes sure you only pay the tax that you need to. Knowing how to bring forward losses and use other reliefs can give you tax savings in future tax years too.
The time not spent dealing with your tax return can be used however you choose. Just like using any other service if you pay someone else to do it you don’t have to.
HMRC can make enquiries into the accuracy of your tax return and if they find mistakes penalties can be handed out.
Your accountant is there to guide you on any accuracy and compliance issues and support you through an HMRC enquiry if it ever happens.
Not meeting an HMRC deadline usually means a penalty either for late filing or for not paying what you owe on time (or both).
Self assessment tax return deadlines are strict and accountants know it so they’ll do what they can to make sure you are on time.
If after your tax return is submitted you have a tax bill your accountant will let you know the date HMRC expect to be paid by, how to pay and any payment options for example Time to Pay.
Tax planning is sensible especially if you are thinking about making changes in the future. Your accountant can highlight and explain what’s possible so you can get the most out of any opportunities.
Your accountant will use software that is approved by HMRC and submit your tax return online by your filing date.
Making tax digital is bringing with it changes to how self assessment tax returns are submitted and the way in which you keep records.
MTD for ITSA compatible software will be used by your accountant meaning you don’t need to invest in third party accountancy software for reporting and record keeping.
Making tax digital is being rolled out by HMRC over a number of years and is effecting different groups of people at different times.
For example from April 2026 HMRC are expecting sole traders and landlords with an income of £50,000 or more to meet MTD for ITSA requirements.
Your accountant will keep you informed about your obligations under MTD and take care of any new digital filing and record keeping requirements.
Getting a late Self Assessment tax return filing penalty can happen to anyone. The best course of action is to submit your tax return as soon as possible and then appeal any late penalties if you can.
In many circumstances HMRC can cancel late filing penalties if you have a reasonable excuse. A tax return accountant can help you appeal any late penalties and cancel any tax returns that do not need to be completed.
You can read our free Self Assessment tax return guide to understand more about tax returns.